Personally I think that some of my attempts have been successful - but I'm continuing on because I exist in one of the worlds where I survive my attempts - this only strengthens my resolve (to see if I can actually cease to exist from my point of view).

There is a problem with this theory though.
What happance when someone old is dieing?
He is old in every singel paraller univarse, which mean he die in all of them
maybe not in the same time be he dies eventualy becouse out biological
boddy cant live forever. Then what happance?

I thought about it a lot, what if i died and i am not even aware of that?
My "self" transfared to a paraller world where i live, if so, it should
mean that we are immortals, becouse every time we die, we just transfared
to another univarse.

The Copenhagen Interpretation is the accepted philosophy in the physics realm - but parallel universes can exist in that interpretation as well. The whole idea behind the many worlds interpretation is that in at least one universe no matter how old you are or what happens in other universes your consciousness remains intact - because no matter how improbable there is still a slight probability that you survive given any situation (including old age) and that any probability that exists is a branch taken given every moment in time which spawns an infinite number of parallel universes.